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Amorphous layer around aragonite platelets in nacre.

ABSTRACT: We reveal that the aragonite CaCO3 platelets in nacre of Haliotis laevigata are covered with a continuous layer of disordered amorphous CaCO3 and that there is no protein interaction with this layer. This finding contradicts classical paradigms of biomineralization, e.g., an epitaxial match between the structural organic matrix and the formed mineral. This finding also highlights the role of physicochemical effects in morphogenesis, complementing the previously assumed total control by biomolecules and bioprocesses, with many implications in nanotechnology and materials science.

SUBMITTER: Nassif N

PROVIDER: S-EPMC1200266 | biostudies-literature | 2005 Sep

REPOSITORIES: biostudies-literature

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Amorphous layer around aragonite platelets in nacre.

Nassif Nadine N Pinna Nicola N Gehrke Nicole N Antonietti Markus M Jäger Christian C Cölfen Helmut H

Proceedings of the National Academy of Sciences of the United States of America 20050829 36

We reveal that the aragonite CaCO3 platelets in nacre of Haliotis laevigata are covered with a continuous layer of disordered amorphous CaCO3 and that there is no protein interaction with this layer. This finding contradicts classical paradigms of biomineralization, e.g., an epitaxial match between the structural organic matrix and the formed mineral. This finding also highlights the role of physicochemical effects in morphogenesis, complementing the previously assumed total control by biomolecu ...[more]

PMID: 16129830

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